Update the timer to properly handle recursion and deep call stacks

haversine_02/include/profiler/timer.h

@@ -27,9 +27,10 @@ typedef struct sample profiler_sample_t;
 
 struct sample {
   const char *title;
+  u64 first_start;
   u64 start;
-  u64 duration;
-  u64 children_duration;
+  u64 exclusive_time;
+  u64 children_time;
   u64 hit_count;
   profiler_sample_t *parent;
 };